gdb/testsuite/gdb.trace/range-stepping.c

   1 /* This testcase is part of GDB, the GNU debugger.
   2
   3    Copyright 2013-2020 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #ifdef SYMBOL_PREFIX
  19 #define SYMBOL(str)     SYMBOL_PREFIX #str
  20 #else
  21 #define SYMBOL(str)     #str
  22 #endif
  23
  24 /* `set_point' further below is the label where we'll set tracepoints
  25    at.  The insn at the label must the large enough to fit a fast
  26    tracepoint jump.  */
  27 #if (defined __x86_64__ || defined __i386__)
  28 #  define NOP "   .byte 0xe9,0x00,0x00,0x00,0x00\n" /* jmp $+5 (5-byte nop) */
  29 #elif (defined __aarch64__)
  30 #  define NOP "    nop\n"
  31 #else
  32 #  define NOP "" /* port me */
  33 #endif
  34
  35 int
  36 main(void)
  37 {
  38   /* Note: 'volatile' is used to make sure the compiler doesn't
  39      optimize out these variables.  We want to be sure instructions
  40      are generated for accesses.  */
  41   volatile int i = 0;
  42
  43   /* Generate a single line with a label in the middle where we can
  44      place either a trap tracepoint or a fast tracepoint.  */
  45 #define LINE_WITH_FAST_TRACEPOINT                                       \
  46   do {                                                                  \
  47     i = 1;                                                              \
  48     asm ("    .global " SYMBOL (set_point) "\n"                 \
  49          SYMBOL (set_point) ":\n"                                       \
  50          NOP                                                            \
  51     );                                                                  \
  52     i = 2;                                                              \
  53  } while (0)
  54
  55   LINE_WITH_FAST_TRACEPOINT; /* location 1 */
  56
  57   return 0;
  58 }